During the operation of open-end spinning devices, upon their spinning, due to the constant contact of the fibers fed to the spinning rotor with the walls of the spinning rotor, and due to the fiber dust that arises, contaminants and deposits on the spinning rotor arise. This may impair the quality of the yarn that is spun, and therefore must be removed at regular intervals. Likewise, upon piecing after an interruption of the spinning process, for example after a yarn break, it is necessary to remove from it the fiber material that is still found in the spinning rotor, in order to ensure unvarying conditions regarding fiber quantity upon piecing and thus a uniform quality of the yarn that is spun. Therefore, various devices for rotor cleaning, which clean spinning rotors by means of mechanically contacting or pneumatic cleaning elements, are already known in the state of the art.
A cleaning head with a cleaning brush is known from U.S. Pat. No. 4,480,433. If such cleaning head is located in its working position fed to the spinning rotor, the bristles of the cleaning head engage in the rotor groove and free it from the contaminants adhering there by turning the brush head. However, with such cleaning devices provided with a brush, there is a risk that the detached contaminants will clog the bristles of the cleaning brush within a short time. Therefore, after a short time, the cleaning head must be replaced or even subjected to a cleaning.
By contrast, DE 26 18 094 A1 shows a cleaning head with a scraper element that is adjusted to the contour of the rotor groove and can be fed to the rotor groove. However, only the rotor groove itself can be cleaned by means of the scraper element. While the rotor groove of a spinning rotor is subjected, to a certain extent, to the depositing of dirt, contaminants may also arise in the area of the slide wall.
Therefore, EP 1 327 708 A2 proposes a cleaning device with a cleaning head, which cleans the rotor groove with a first cleaning element and the rotor slide wall with a second cleaning element. Thereby, a preferential embodiment of EP 1 327 708 A2 provides two groups of bristles, wherein a first group is to clean the rotor groove and a second group is to clean the side wall of the spinning rotor. In addition, one or two compressed air nozzles can be arranged, which support the cleaning of the rotor groove and/or the fiber slide wall, and further ensure the transporting away of the detached dirt.
However, it has been found that such contaminants arise not only in the area of the rotor groove and the fiber slide wall. Moreover, in the area directly at the open edge of the spinning rotor, over the course of time, such deposits (but those that are not picked up by conventional cleaning devices) arise. Such contaminants are suddenly and unexpectedly detached during the spinning process, or crumble and then fall into the fiber collection groove. This leads not only to quality impairments of the yarn that is drawn, but also quite frequently to yarn breaks. In particular, this problem arises in the processing of polyester fibers, since, due to the various chemical additives for spinning preparation, these particularly tend to produce deposits on the fiber slide wall of the spinning rotor.